Electrical switch



ELECTRICAL SWITCH Filed Aug. 21, 1926 Z). JJW J ll c27 0? Patented June 5, 1928.

UNITED STATES 1,672,791 PATENT, OFFICE.

v WILFRED SYLVESTER THIMBLETHORIEE, OF LONDON, ENGLAND.

ELECTRICAL SWITCH.

Application filed August '21, 1926, Serial No. 130,716, and in Great Britain September 4, 1925.

This invention relates to improvements in electrical switches and has for its object to provide an improved form of two-way delayed action switch particularly useful in electrical signalling work and apparatus.

According to the invention the switch is provided with an operating lever mounted for lateral movement in two directions which is connected with a clockwork or similar mechanism in such a manner that when the lever is moved in either direction to close an electrical circuit, the circuit remains closed for a predetermined time and is then automatically broken and the switch lever returned to the original or open circuit position.

Further, the apparatus may be so arranged that while the switch is holding the circuit closed, the said circuit may be automatically interrupted to produce a series of makes and breaks in the circuit. includes lamps, the lamps may be flashed intermittently and automatically throughout a predetermined period.

In a suitable construction, the operating lever of the switch is pivotally mounted with one end engaging a cam, the latter being connected to a train of clockwork and under the influence of a spring.

With this arrangement if the lever is moved in either directionto close a circuit the cam is moved against the spring and the latter then moves the cam, causing the clockwork train to operate which causes the switch lever to be returned slowly to its original or open circuit position. The electrical contacts are so arranged that the circuit remains closed until the switch lever is back into its open circuit position, when the circuit is broken.

Further, the clockwork train may be fitted with an escapement or the like arranged to act as a circuit breaker when the clockwork is in motion, causing the circuit closed by the switch to be intermittently and automatically interrupted during the movement of the switch lever from the closed to'the open circuit position.

To enable the invention to be fully understood it will now be described by reference to the accompanying drawings in which Fig. 1 is a side elevation of a switch constructed according to the invention with one side of the casing removed, the switch lever being in the no circuit position, and

Fig. 2 is an end elevation thereof.

Thus, if the circuit Fig. 3 is a diagrammatic plan view of the base of the switch showing the electrical connections. I

As shown the switch comprises a casing 4 having a clockwork train mounted therein, the wheel 5 being the driving wheel and the wheel 6 the escapement wheel, the anchor 7 being driven from the balance wheel (not shown) in the usual manner. The bottom 8 of the casing is of insulating material and pivoted thereto at 9 is the switch operating lever 10 adapted to be moved over the contacts 11, 12 as hereinafter described. Pivoted to the casing at 13 is a cam 14 having a V-shaped groove 15 in the face thereof, the top of the cam engaging beneath a spring 16, one end of which (not shown) is anchored to the casing. The cam also carries a preferably spring pawl 17 engaging the driving wheel 5. The lever 10 is fitted with a roller or member 18 which when the lever is in the central orno-circuit position rests in the groove 15 as shown in Fig. 2.

With this arrangement, if the lever 10 is moved in the direction of the arrow A to complete a circuit, Fig. '3, the cam 14 is raised against the pressure of the spring 16, the pawl 17 clicking over the teeth of the driving wheel 5. As soon as the lever 10 is released the spring 16 depresses the cam, the latter driving the clock train through the pawl 17 and sincev the roller 18 is in contact with one side of the groove 15 of the cam,

secured to the spindle of the anchor 7 to make and break the circuit when the clock train is operated as will be readily understood.

Referring to Fig. 3 it will be seen that the switch illustrated is a two-way switch adapted to operate two circuits 22, 23. The terminals of the contact springs 19, 20 are indicated at 24, 25, respectively, theswitch lever being electrically connected to the contact 25 by the lead 26. Two contacts 11, 12, for left and right movements of the lever 10 are provided, the battery C being connected as shown. v

bbviously the switch .may be used to control any'number of circuits by suitably arranging the circuits and contacts with or without the intermittent contact breaking device. Further, the switch may be arranged so that the lever 10 may have an up and down motion instead of a lateral movement, as shown or a combined up and down motion and lateral movement.

If desired, the cam may be' provided with a part which will positively start the operation of the escapement as soon as the lever is moved to the desired contact position to ensure correct working of the device.

The cam may be formed or stamped in one piece and so designed that the pawl and main or driving spring are-formed intergral therewith.

The duration of the switch contact may be varied by regulating the movement ofthe lever and the size and shape of the cam.

Obviously the present invention may be applied to electrical or other signalling de- Vices and to many purposes for which it is desired to employ a time switch, with or without intermittent breaking of the circuit controlled by the switch.

Having thus described the nature of the said invention and the best means I lmow of carrying the same into practical effect, I claim 1. In an electric switch and in combination, a base electrical contacts on the base, an operating lever pivoted on the base for movement laterally in two directions to control the contacts, a cam having a V-shaped groove through which the operating lever passes, a clockwork train, a spring-pressing on the cam, and a pawl on the cam engaging a wheel of the clockwork train to drive same, the arrangement being such that when the lever is moved laterally to close a circuit.

in either direction the clockwork is set in motion to return the lever to the no-circuit position.

2. In an electric switch and in combination, a base, electrical contacts on the base, an operating lever pivoted on the base, a cam engaging the lever, a clockwork train, driv ing means for the clockwork train carried by the cam, an escapement governing the clockwork train and an electrical circuit interrupter driven by the escapement.

3. In an electric switch and in combination, a base, electrical contacts on the base,

an operating lever pivoted on the base, a cam engaging the lever, a clockworktrain,

driving means for the clockwork train cartrain carried.- by the cam, a spring pressing on the cam, an escapement governing the clockwork train and means operated by the escapement for making and breaking a circuit closed by the operating lever.

5. An electrical switch arrangement, comprising opposed contacts, a lever adapted to be moved laterally in either direction to engage one or other of the opposed contacts, and time-o erated means adapted to be set by the shi ing of the lever in either direction for shifting said lever from either side to the neutral position between and out ofengagement with said contacts irrespective of which lateral position the lever occupies.

In testimony whereof I have signed my name to this specification.

WILFRED SYLVESTER THIMBLETHORPE. 

